The present invention relates to a controller for an internal combustion engine and a method for controlling an internal combustion engine.
Japanese Laid-Open Patent Publication No. 2013-234673 discloses a V-type eight-cylinder internal combustion engine. The internal combustion engine includes a first bank that has four cylinders configured to be a first cylinder group and a second bank that has four cylinders configured to be a second cylinder group. Each cylinder of the first bank is supplied with fuel from a first fuel injection valve that corresponds thereto. Each cylinder of the second bank is supplied with fuel from a second fuel injection valve that corresponds thereto. Additionally, the air-fuel ratio of exhaust gases discharged from the four cylinders of the first bank is detected by a first air-fuel ratio sensor. The air-fuel ratio of exhaust gases discharged from the four cylinders of the second bank is detected by a second air-fuel ratio sensor.
Fuel injections from the first fuel injection valve and from the second fuel injection valve are controlled by a controller. The controller calculates a fuel injection amount required during one combustion cycle in accordance with a running state of the internal combustion engine. Additionally, the controller determines the number of times that fuel is injected during one combustion cycle in accordance with the running state of the internal combustion engine and the calculated fuel injection amount.